The present invention relates to a feed magazine of part-movable design suitable for automatic machines used in the manufacture of cans comprising a body of cylindrical (or other) geometry and two disks, one at either end of the body, constituting the lid and base of the can. The function of the magazine in question is to dispense the disks to the machine singly and in succession.
The prior art embraces lid magazines for automatic machines of the type mentioned above, consisting in a cylinder disposed preferably with the axis of its endmost part angled from the vertical, internally of which the lids (or bases) are stacked one on top of another and restrained by a retractable blade; the lids are released individually by the blade and taken up by a device comprising a circular wheel, likewise disposed preferably with its axis angled from the vertical, which affords a peripheral cam profile contoured such that each successive lid can be eased down onto a horizontal surface coinciding with a transfer station; from here, the lids are conveyed simultaneously with respective can bodies to a successive assembly and seam-folding station.
The upright cylinder of the magazine, which lies almost entirely outside the compass of the machine and may be rectilinear or otherwise, is anchored rigidly to a bracket associated with the machine, in a position facing the device by which the lids (or bases) are released. The dispensing end of the magazine comprises a set of guide bars (preferably four) adjustable for position in a radial direction so as to accommodate different sizes of lids, or bases, and creating what is effectively a channel affording access to the machine. A sensor installed at the dispensing end of the magazine, immediately below the surface onto which the single lids are lowered, serves to verify the presence or absence of the lids, and, in the event that a lid is either missing or incorrectly positioned, to inhibit the operation of the machine or suspend the flow of can bodies to the seam-folding station.
Such magazines nonetheless betray certain drawbacks deriving from the conventional type of embodiment adopted, that is to say, from the fact that all the component parts of the terminal dispensing section are permanently associated with the fixed structure of the machine, i.e. rigidly connected by means of bolts or other mechanical fasteners which are not readily disassembled. However, given that automatic machines of the type in question are operated at a particularly high production tempo (hence with a notably high throughput of lids), there is a much increased risk that two or more lids might become jammed at the dispensing end of the magazine, with the result that successive lids will buckle and the entire machine is brought to a standstill.
To remove the obstruction, the operator must first insert a rod transversely into and across the end of the magazine in order to prevent any remaining lids from descending further, and then proceed to dismantle all such components of the magazine as are associated with the machine. Needless to say, such an operation requires considerable time to effect (time wasted, in terms of production) and its impact is clearly unacceptable in the context of the operating speeds for which machines of this description are intended, and the levels of output typically expected.
Accordingly, the object of the present invention is to overcome the drawbacks in question by providing a magazine for can lids/bases of which one section is retractable and rotatable, so as to allow swift and secure maintenance and adjustment.